I think people join orgs for which they pay, therefore later to display, is an attempt to get them more credibility when they think what they have so far is not adequate.

I have never had a problem with teaching and my credentials. I never display anymore than what I am. That said, I do not go forth and display my identity on open forum for the main reason of political strife within the martial art systems I was among.

Furthermore, there are other schools that I know of, and their instructors, and despite not training with these, I can fully recommend to anyone who is more interested in anything apart from what I do. (They in reversal)

To the OP, Raul;

This subject became an issue during the 70's when a senator (whom was a student of Jhoon Rhee) tried to use his influence in Congress to find or establish a regulation for martial arts.